A PROCESS FOR THE PRODUCTION OF A STRUCTURED COMPOSITE PIGMENTARY MATERIAL IN THE FORM OF A DISPERSION COMPRISES MIXING AN AQUEOUS DISPERSION OF INORGANIC PIGMENTARY PARTICLES AND AN AQUEOUS DISPERSION OF POLYVINYL CHLORIDE (PVC) PARTICLES. THE INORGANIC PIGMENT PARTICLES CARRY A POSITIVE SURFACE CHARGE AND THE PVC PARTICLES CARRY A NEGATIVE SURFACE CHARGE AND THE PARTICLES IN THE COMPOSITE ARE HELD IN ASSOCIATION AS A RESULT OF THESE CHARGES. THE INORGANIC PIGMENT PARTICLES AND PVC PARTICLES ARE MIXED IN THE PRESENCE OF A SURFACTANT SYSTEM WHICH PROVIDES BOTH ANIONIC AND STERIC STABILISATION. IN ONE EMBODIMENT THE SURFACTANT SYSTEM COMPRISES A NONIONIC SURFACTANT HAVING AN HLB VALUE GREATER THAN 12 AND AT LEAST 2BY WEIGHT OF AN ANIONIC SURFACTANT WITH RESPECT TO THE WEIGHT OF PVC PARTICLES. IN A SECOND EMBODIMENT THE SURFACTANT SYSTEM COMPRISES AT LEAST 2BY WEIGHT (WITH RESPECT TO PVC) OF ONE OF MORE SURFACTANTS PROVIDING ANIONIC AND STERIC STABILISATION AND BEING ETHYLENE OXIDE CONDENSATION HAVING A POLYOXYETHYLENE CHAIN WITH AN AVERAGE LENGTH OF AT LEAST 8 OXYETHYLENE UNITS. THE PRODUCT IS USEFUL IN PAINTS AND PROVIDES IMPROVED OPACITY COMPARED TO CONVENTIONAL PIGMENTS AND IMPROVED GLOSS COMPARED TO KNOWN STRUCTURED COMPOSITE PIGMENTS.
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